Conventionally, a device for raising/lowering a windowpane of a vehicle is constructed, such that the windowpane is raised or lowered through an elevating mechanism by transmitting rotary driving force by an electric motor to the elevating mechanism. In such a raising/lowering device, a driving voltage is simply applied to the electric motor according to rising or descending of the windowpane. Thus, when the windowpane is lowered to a bottom lock position, the windowpane is mechanically constrained by a stopper, thereby applying excessive impact force to a drive system. Accordingly, there is a problem of an occurrence of an offensive impulsive sound, as well as deterioration in durability of the drive system.
In order to avoid making an impact, which results in serious deterioration in the durability of the drive system, it is proposed to stop rotation of the electric motor by stopping a drive of the electric motor immediately before the bottom lock position and by lowering the windowpane to the bottom lock position through inertia (e.g., JP2577092 Y2 (pp. 3-6, FIGS. 11, 12)). However, since such an art still employs a configuration to stop the windowpane at the bottom lock position, an operation stop noise is inevitably made when the windowpane stops. In addition, when an operation of the motor is stopped before the bottom lock position, a stop position of the windowpane varies, thereby stopping the windowpane above a belt molding, under an influence of a variation in a load because of deterioration due to age and the like.